Apparatus for treating liquids



July28, 1942. r MacLEAN 2,290,980

APPARATUS FOR TREATING L'IQUIDS Filed Dec. 24, 1940 r IRE/1 TED PRODUCT FRESH l FEAGF/VT I 50 H 59 L f5 I 7 8 14 J W 74 4 I? I 52 l. H

10 r q 3 l 1.? 74 if; ,3 I b 214 53 FRESH REA GEN 7' RA W PROD UC, E5 TEEN D REC/M004 TED SPENT REAGEN REAGENT 55 INVENTOR.

60/Q 0/Z fill/[Lam M M w m ATTOR/V Y5 Patented July 28, 1942 2,290,980 7 APPARATUS FOR TREATING LIQUIDS Gordon MacLean, Flushing, N. Y., assignor to The Turbo-Mixer Corporation, New York, N. Y., a corporation of New York Application December 24, 1940,'Se1'ial No. 371,571

6 Claims.

This invention relates to apparatus for treating liquids, including solids in suspension which can be handled in much the same mannet as other liquids. In the usual case, a raw liquid material is treated with one or more liquid reagents which are immiscible with the raw material being treated. However, either the raw material or the reagent, or both, may be a finely divided solid material in suspension in a liquid; and I use the term liquid to include such suspensions. In the case of a finely divided solid reagent, or a finely divided raw material, the finely divided solid may be previously prepared in a liquid suspension, or it may be fed into the apparatus in finely divided solid form and the liquid suspension formed in the apparatus itself.

While the invention is one of general applicability as above pointed out, it will be convenient to disclose and discuss it in one particular form intended primarily for one particular use. To this end the invention will be disclosed and discussed as applied to an apparatus for treating raw gasoline to remove impurities such as hydrogen sulphide and mercaptans.

The prior art practice is to treat the gasoline by prolonged and intimate intermixture of the reagent with the gasoline in a series of orifice columns. These columns consist of a succession of flanged pipe sections separated by perforated plates. The use of such columns requires a large amount of power to pump the gasoline through the numerous perforated plates; and to obtain sufficient mixing action, the rate of flow through the columns must be maintained at the value for which the colunms are designed. At times the output of the gasoline still may fall off so that the amount of raw gasoline available is insufli-cient to keep the flow through the orifice columns at a rate sufiiciently high for proper mixing action in the orifice columns.

- A general object of the present invention is to provide liquid treating apparatus of increased effectiveness and reduced power requirements.

Another object of the invention is to provide liquid treating apparatus which is effective and efiicient in its treating function despite wide Variations in the rate of flow of the liquid to and from the apparatus.

A still cf-urther object of the invention is to provide continuous liquid treating apparatus which efiectively produces intimate and prolonged mixture of the reagent with the liquid being treated without serious loss of pressure head from the flow through the apparatus.

Various additional objects of the invention will be obvious from the following disclosure.

The drawing is a diagrammatic figure showing apparatus embodying the present invention.

A vertical cylindrical casing I is sub-divided by partitions 2, 3 and 4 into four superimposed mixing chambers 5, 6, I and 8., A vertical mixing shaft 9 is common to all of the chambers 5, 6, I and 8 and carries and drives four mixing impellers II, I2, I3 and I4. These impellers have outwardly extending curved blades and are of conventional design. One impeller is located in each of the chambers 5, 6, I and 8, as shown. Surrounding the respective impellers are stationary deflector rings Ila, I2a, I3a, and Ida. These deflector rings are of conventional design consisting essentially of an annular series of spaced vertical deflecting blades of curved form. Bearings for shaft 9 are provided at I5, I6, I! and I8. A stufling gland is associated with bearing I5, and the other bearings prevent any appreciable flow direct from mixing chamber to mixing chamber. Shaft 9 may be driven in any suitable way, as by gear head It which receives power from a power shaft Illa. Other suitable driving mechanism for shaft 9 is that shown in U. S. Patent, Petry, 2,151,146, dated March 21, 1939.

A second vertical cylindrical casing 20 is subdivided by partitions 2|, 22 and 23 into a plurality of superimposed settling chambers 24, 25, 26 and 21. The settling chambers are associated with the mixing chambers by means of a system of pipes which .will now be described.

The respective mixing chambers 6, I and 8 are provided with inlet pipes 6a, la and 8a and with outlet pipes 61), lb, and 81). Each of the inlet pipes leads from the top of one of the settling chambers and conducts the liquid to a point adjacent to the low pressure zone of the impeller in the mixing compartment. Each of the outlet pipes 6b, Ib and 8b conducts the liquid from a mixing compartment to a settling compartment. Outlet pipes 51;, 6b and lb discharge the liquid quietly, as from funnel-like end sections A, each having a screen B at its mouth. Outlet pipe 8b discharges beneath a. bafile 20 which prevents the liquid from surging upwardly in chamber 24. Connected to inlet pipe 8a is a valve controlled supply pipe 30 for [fresh reagent. A pipe 24a connects the bottom of settling chamber 24 with inlet pipe Ia and a similar pipe 25a connects the bottom of settling chamber 25 with inlet Pipe 60.. Flow-controlling manually adjustable valves 24b and 25b are provided for pipes 24a and 25a respectivelv.

Mixing chamber 5 is connected by outlet pipe 51) with settling chamber 21, and a return pipe 21a connects the bottom of settling chamber 21 with a point adjacent to the low pressure zone produced by impeller H in mixing chamber 5. A suitable pump 35 is connected to deliver the raw product to be treated through ,valve control pipe 35 to mixing chamber 5.

Assuming the apparatus to be in operation, the flow through it will now be traced. Raw gasoline is delivered by pump 35, conduit 36, and valve 37 to impeller II. A reagent such as caustic soda solution is also being drawn by impeller ll through pipe 21a, from the bottom of settling tank 27. The reagent and raw gasoline are mixed in impeller II and discharged outwardly through deflector ring Ha. At the same time, the mixture in chamber 5 is being continuously drawn downwardly into the low pressure zone of impeller H and mixed with thefresh liquids coming into chamber 5. Thus the liquids in chamber -5 are being continuously mixed and circulated by impeller l l, fresh gasoline gradually entering through pipe 35 and reagent entering through pipe 2M.

The entry of new liquids through pipes 35 and 21a. causes a corresponding displacement of the old mixture from chamber 5 through outlet pipe 5b into settling chamber 21. In this chamber the gasoline rises to the top, and the reagent settles to the bottom through perforated partition or screen 33 for recirculation to mixing compartment 5.

From the top of chamber 21 gasoline passes through inlet pipe 6a to mixing chamber 6, picking up reagent from pipe 25a. as it passes through pipe 6a. From mixing chamber 6 the gasoline progresses through outlet pipe 51) to settling chamber 25. The reagent settles to the bottom of chamber 25 and is discharged through pipe 40. The gasoline rises to the top of settling chamber 25 and passes through inlet pipe 1a to mixing chamber '1. On the way, the gasoline receives reagent from pipe 24a. Leaving mixing chamber 1, the mixed gasoline and reagent pass to settling chamber 25. Again the reagent'settles to the bottom and the gasoline passes from the top of chamber 25 through inlet pipe 8a to mixing chamber 8. On the way the gasoline receives fresh reagent from pipe 30. Leaving mixing chamber 8 the mixed gasoline and reagent pass through outlet pipe 822 to settling chamber- 24. The reagent settles .to the bottom and the treated gasoline rises through perforated partition or screen 39 and is discharged-by the treating apparatus through pipe 4L Small valve-controlled by-pass pipes 50, 6c and To pass gas and air directly from mixingcompartment to mixing compartment, but the flow through these is so limited as to prevent any appreciableby-passing of the gasoline itself. Air relief valves may also be provided to blow off air or gas which may accumulate at any particular points in the system. By way of illustration such relief valves areshown at 50, 5|, 52, 53 and 54. However, these valves can in many instances be rendered unnecessary by discharging the gasoline from the top zones of various chambers, so that any air or gas is carried out with the gasoline. Such gasoline discharge is shown from chambers 24, 25, 25 and 21, so relief valves 5-l, 52, 53 and 54 are merely extra precautions.

and fresh caustic is admitted through valve 56.

Mixing chambers 6, 7 and 8 and settling chambers 24, and 25, with the various connecting pipes, constitute a system through which the gasoline and caustic solution are moved in V counter-current relation to remove the mercaptans. In mixing chamber 6 the gasoline is acted upon by caustic which has already been in mixing chambers 1 and 8. In mixing chamber 1 the gasoline is acted upon by caustic which has already been in mixing chamber 8. In mixing chamber 8 the gasoline is acted upon by fresh caustic. The spent caustic from this countercurrent system is discharged through adjustable valve 60 to be reclaimed.

It will be seen that the apparatus shown provides for continuous treatment, which may include a separate preliminary treatment (chambers 5 and 21) and a prolonged counter-current treatment (chambers 6, 1, 8, 24, 25 and 26). For some purposes a separate final treatment is provided by adding a recirculation stage (similar to chambers 5 and 21) to which the liquid passes after leaving the counter-current system of chambers. Of course, different reagents may be used in the preliminary treatment, the counter-current treatment, and the final treatment (if any), depending upon the nature of the raw material being treated and the type of results which are to be achieved.

While I have shown three stages in the counter current system, two stages will suffice for some purposes, and more than three can be used if desired. Each of the mixing impellers ll, I2, l3 and I4 produces some suction effect and this compensates for loss of pressure head due to fiuid friction in the pipes, etc. Thus, the addition of more stages to the apparatus does not necessitate additional outside pumping. The intimate intermixture of the reagents with the liquid is effected by the impellers and therefore the mixing action is not impaired by a decreased rate of flow to and from the apparatus, as is the case with an orifice column.

I prefer to form the mixing chambers in a common exterior casing, and likewise for the settling chambers. However, separate tanks may be used to provide the different chambers, particularly the settling chambers.

In compliance with the patent statutes I have disclosed the best form in which I have contemplated applying my invention, but it will be understood that the disclosure is illustrative only, and not limiting.

I claim:

1. Treating apparatus comprising: a first vertical casing; partitions subdividing said casing into a plurality of superimposed mixing chambers; a Vertical drive shaft common 'to the mixing chambers; a plurality of rotary mixing devices mounted on and driven by said shaft, one mixing device being in each of the mixing chambers; a second vertical casing, partitions dividing said second casing into a plurality of superimposed settling chambers companion to said mixing chambers; and means to pass two kinds of liquids through the apparatus in countercurrent relation, each liquid being alternately in a mixing chamber and intermediately in a settling chamber, said means including outlet conduits from the mixing chambers to the respective settling chambers and including inlet conduitsfrom the bottoms of the settling chambers to the preceding mixing chambers respectively.

2. Apparatus as in claim 1 in which by-passes are provided to by-pass gas directly from mixing chamber to mixing chamber.

3. Apparatus as in claim 1 in which by-passes are provided to by-pass gas directly from mixing chamber to mixing chamber, each by-pass being provided with an adjustable valve to control the flow through it.

4. Apparatus 'as in claim 1 in which a separate mixing-and-scttling stage is provided in addition to the counter-current system specified in claim 16.

5. Apparatus as in claim 1 in which the outlet conduits are provided with funnel-like end sections through which they discharge into the settling chambers.

6. Apparatus as in claim 1 in which the outlet conduits are provided with funnel-like end sections, the mouths of which are provided with screens through which the conduits discharge into the settling chambers.

GORDON MAcLEAN.

GERTIFI GATE OF CORRECT ION Patent no; 2,290,980. Jul 28, 19m.

GORDON MacLEAN.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 5, sec- 0nd column, line 6, claimh, for the claim reference numeral "16" read --1-; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 22nd day of September, A. D. l9LL2.

I Henry Van Arsdale, (Seal) Acting Commissioner of Patents. 

